Control email deliveries in Rails with a custom Interceptor

You can easily tell Rails to control email delivering with a custom mailer interceptor, all you need to do is to implement the class method `delivering_email`:

```ruby
class DeliverOrNotEmailInterceptor
  def self.delivering_email(email)
    mail.perform_deliveries = !email.to.end_with?('special-domain.com')
  end
end

# config/initializer/email_interceptors.rb
ActionMailer::Base.register_interceptor(DeliverOrNotEmailInterceptor)
```

Edwin Cruz
May 4, 2021